New disk for existing VM

"Disk offline with error – the disk is offline because of a policy set by an administrator"

After adding a new hard drive to an existing VM, it will show as offline, this can be corrected using the steps below in the diskpart cmd prompt
san policy=OnlineAll 
This will result in the following message: Diskpart successfully changed the SAN policy for the current operating system.
list disk
Check the number of any offline disks and select them
select disk 1
attributes disk clear readonly
online disk
The disk will now be available in Disk Management.